scribner



(No Model.) 2 Sheets-Sheet 1.

O. E. SORIBNER;

' TRANSFERSYSTBM- FOR SWITGHBOARDS.

- Patented Au .(No Mode-1'.) 2 Sheets Sheet' 2.:

i o. S'GRIBNER.

TRANSFER SYSTEM FOR SWITGHBOARDS;

No. 502,771. I Patented Aug. 8, 1893. x

Jzvuio'w I Q IZBSEScIZbwr CHARLES E. SORIBNER, OF CHICAGO,

" PATENT QEFIGE.

ILLINOIS, ASSIGNOR TO THE'WESTERN ELECTRIC COMPANY, OF SAME PLACE.

TRANSFER SYSTEM SYVITCH BOARDS.

sPEcIFIcAtrIon forming part of Letters No. o2,7'71,' datedAug'ust s, 1893.

1 Application filed October 27, 1890. Serial No. 369,405. (No model.)

To all whom/flit may concern.-

Be it known that LCHARLES E. SCRIBNER, a citizen of theUnitejd States, residing at Chi cage, in thefcountyfof'Gook and'State of Illi- 5 nois, have invented acertain new and useful Improvement in Transfer Systems for Switchboards, (Case No. 232,) of which the following is a full, clear, concise, and exact description,

reference being bad to the accompanying Io drawings, forming a part of this specification. My invention relates to telephone exchange systernsin which standard or table switch boards are employed, each table or switch board having switches and annunciators for I 5 a different set or group of lines; several such switch boards or tables may be used in the same exchange with means for transferring the connections between the difierent switch boards or tables. Several different transfer :0 systems-have been heretofore employed in such exchanges. Each operator is provided with a sufficient number of transfer wire connections and suitable apparatus extending to each other operator of the exchange to enable her to transact the business originating at her table.

My invention herein relates tosuch transfer apparatus andcircuits, and its objects are, first, to enable an operator at one board to throw her subscriber into connection with the operator of another board, andby the act of such connection to indicate upon an annunciator at the other board that such acounection has been made; second, to enable the operator at the second board to complete such connection and by the act of completing the connection to indicate to the operator at the first board that-such has been done; third, my invention comprises circuits for the dilferent 0 subscribers groups upon difierent switch boards and transfer apparatus consisting of different transfer wires connected between the boards, each separate transfer connection comprising two clearing out annunciators so arranged that only one of said clearing out annunciators will be included 'inthe circuit while the other clearing out annunciator will be brought into circuit on the removal of the first; and, fourth, the provision of circuits and annunciators to give the operators warning of any accidental disconnection of the connection before the use of such connection has terminated, consisting in the switching apparatus, whereby a battery is closed through the one or the other of the clearing out annunciators as the case may be as one or the other of the plugs is accidentally removed. v My invention will be more readily understood by reference to theaccompanying draw- I ings, in which- "Figure 1 is a diagram illustrative of two telephone lines, the different switch boards of the same exchange connected together, one of my transfer connections uniting said lines. Fig. 2isaside elevation of the transfer switch. Fig. 3 is a View from belowof the same. Fig. 4. is a side elevation in section of the listening key operated by the plug. Fig. 5 is a front elevation thereof. 5 Fig. 6 is a perspec- 7o tive view showing the slot through one of the spring and rubber projections through. the same which is mounted upon another of the springs.

The transfer switch as shown in Figs. 2 and 7 5 3 is of well known construction. A plug in sorted therein completes a connection between the spring and the plug, the movement of this main spring servingto close a separate set of contactswith which the switch is provided.

The listening key shown in Figs. 4:, 5 and 6 is a form heretofore invented by me and shown in one or more of my pending applications.

Referring now to Fig. l the subscribers station a is provided with the usual telephone outfit and is connected by wire I) with an ordinary switch 0 upon one of the switch boards of the exchange, and thence in the usual manner through individual annunciator d. go It will be understood that a group of telephone lines will thus be connected with each boardsay a hundred. The operator will be provided with the required numberof cords and plugs e f and with the usual telephone 5 and signaling apparatus. The subscribers station g is also providedwiththe usual subscribers outfit. The line It extends from ground at station 9 through an ordinary spring jack switch 1' and thus in the usual I00 manner through individual annunciator is to ground. Station 9 and its line it and its" switch 'i and annunciator may be considered as belonging to a group or switch board distinct from that of station a, and my invention relates more particularly to the means of making the connections and disconnections between two such stationsas station ct and station gof two separate groups of lines, or of two separate switch boards; such transfer apparatus being adapted to be used in connection with the ordinary pairs of cords.

and plugs and telephone outfits of the different operators. I have shown in Fig. 1 only one such transfer wire and its connections from each operators table or outfit 1 to the other operators table or outfit 2. Thus by means of the transfer switch? and its connections operator 1 may transfer any line of her group to the operator at station 2 to enable the operator at station 2 to complete the connection with the line called for; by means of transfer switch m. The operator at station 2 (being provided with pairs of cords and plugs similar to the pair e f of operator 1) may transfer the connection of any line of her group to operator 1 to permit operator 1 to complete the connection.

I will now describe the manner of making the transfer connections and I will assume that subscriber of station a desires a connection with the subscriber of station g. Subscriber of station afirst operates individual annunciator d and takes down histolophone. Operator 1 answers by inserting plug 6 of a pair in switch 0 as shown and making connection with her telephone by a suitable switch 91. The operator now listening re ceives the order for connection with subscriber of station g; thereupon she inserts the other plugf of the pair in the transfer switch Z of the transfer line extending to the board upon which is placed switch 71 of subscriberv g. The insertion of the plug f serves to opcrate annunciator n and also the transfer annunciator n of operator 2. It will be unwhen plugfis thus inserted may be traced 3 from ground through battery or, through the contacts a of transfer switch Z and thence through transfer annunciator n and thence to the spring 01 of switch and thence to the heel of plug n and thence to the cord a of said plug and thence by wire 12 to the transfer switch 1 and thence as shown through annunciator n to plug e and switch 0 and over line b to ground at the station of subscriber (1. Thus annunciators n and n are brought into the circuit of the battery H The plug f is practically grounded, being connected to earth through the remainder of the cord circuit and the subscribers line hence I term it a grounded terminal plug. The operator 2 seeing the shutter of annunciatorn fall immediately lifts plug 12 from the socket of the switch 72 corresponding to annunciator n 1 to disconnect.

and receiving the order repeated by operator 1 or subscriber a at once inserts a plug a in switch 71, thus completing the connection. As soon as the plug a is lifted from its socket in switch or the circuit of the battery of through annunciator n is opened (the magnet of annunciator n being also de-energized) and thus operator 1 finding that annunciator n will remain up knows that the order has been received and is being attended to by operator 2. Operator 2 having thus completed the connection may throw the lever 91 of switch a so as to disconnect her telephone. thus connected together may be traced from ground at station of subscriber a over line I) through switch 0, pair of plugs cf, over wire a to cord a and plug a and thence through switch '11 over line It to ground at station of subscriber a. Clearing out annunciator n being in the circuit either subscriber by sending current to line may signal operator On removing plug f the contacts n will be opened and hence battery 07. will find circuit through annunciator "n thus notifying operator 2 that the disconnection has been made. The circuit from battery a" may be traced from ground through the battery, thence to spring 41, of switch a and thence through annunciator n and thence through the contact and spring of switch Z, and thence over wire 01 to cord a plug a, switch 'i, wire it and to ground at station of subscriber g. Thus it will be seen that when two telephone lines are connected the clearing out annunciator of the pair of cordsused in making the connection between the switch of the calling line and the transfer switch will nunciator is operated and the calling line disconnected from the transfer switch the transfer annunciator n will be automatically operated to notify the operator at the board of the subscriber called of the clearing out signal; thereupon the operator thus notified will withdraw the connecting plug, as n from the called subscribers switch and restore the same to its normal position in the socket of its switch as n.

I hav,e shown the plug of the listening key 0 of the outfit of operator 1 with its plug resting in its socket, its metallic heel acting as a wedge to separate the spring from its connection with the battery n.

I have not deemed a detail description of the transfer switch as shown in Figs. 2 and 3 necessary. Sufiiceit to saythat a plug being inserted lifts spring 19 from its normal contact q; spring 19 being thus lifted carries contact spring 'r against contact 8. Thus as heretofore described with respect to transfer switch Z the insertion of a plug automatically closes the contact spring r and contacts, that is, closes contacts at of switch Z. VVh'cn the plug is withdrawn the switchassumes the position indicated in Fig. 2, also indicated at switch I m of Fig. 1.

'105 be left in circuit; when this clearing out an- 7 The listening key or switch illustrated in detail in Figs. 4., 5 and 6 I have not deemed necessary to describe in detail.

The connecting plug having a metallic heel electrically connected with the cord normally rests in the socket as shown atswitch o of Fig. 1. On removing this plug from the socket the switch assumesthepositionindicatedat switch 72; of Fig. 1; also indicated in Figs. 4 and 5. By throwing the lever as n the spring tmay be lifted from its contact 25 with the telephone. It will be observed that the contacts n of transfer switch Z will be closed when plug f is inserted, and that when the plug a is resting in its socket in the switching device n the spring n will be in contact with the plug n and hence in connection with its cord 01.

The circuit of battery 00. with respect to the annunciator n is controlled by the transfer switch Z and the switching device n; thus when the plug is removed from transfer switch I and plug a is in its socket there will be no current through annunciator n insert plug f as shown and there will be circuit from battery n through annunciator n remove plug n from its socket and current will be cut off from annunciator n again while plug n is removed from its socket Withdraw plug from transfer switch 1 and current will be restored to annunciator m in other words we have at the different boards a switching device connected in circuit with a battery and an annunciator; no matter what may be the position of these two switching devices a change in the position of the other switch will either disconnect or connect the battery from the annunciator accordingly as the battery is connected or disconnected from the annunciator at the time the change is made. It will be further observed that the circuit of the battery n through annunciator n may be controlled at either switch board by the switching device of the different operators connected therewith, and it matters not what may be the position of either switching device a change of the circuit at either switching device changes the electrical condition of the annunciator.

Having thus described my invention, I claim as new and desire to secure by Letters Patent- 1. A telephone line extending from ground at a subscribers station thereon through an annunciator as n at one board of an exchange and thence through a switching device as n at another board of the exchange and thence through a battery to ground, whereby on opening the circuit at said switching device the battery is disconnected from the annunciator at the first board, substantially as and for the purpose specified.

2. The combination with a telephone line extending from earth at a substation to an exchange and connected with a conductor terminating in a connecting plug thereat, of a spring .jack into which said plug is inserted,

normally separated contact .points on said jack closed together by said plug, and a local branch circuit extending from said terminal plug through an annunciator and said normally open contact points to earth, substantially as described.

3. The combination with a transfer line of a signaling circuit normally closed at the sending end thereof, but adapted to be opened when connection is made with the transfer circuit at that end, and normally open at the receiving end thereof but adapted to be closed when connection is made to that end of the signaling circuit, anindicator at the receiving end and a source of electricity in the signaling circuit, substantially as described.

4.. In combination with the signaling circuit of a transfer line terminating at one end in a spring jack, and at the other end in a terminal plug, of contact points controlled by the spring jack to open the signaling circuit when a plug is inserted into the jack, a cord switch forthe terminal plug adapted to close the signaling circuit when the plug is removed from the socket, and an indicator at the receiving end of the transfer line in the signaling circuit, substantially as described.

5. The combination in a signaling circuit for a transfer system, of a switch at each end thereof adapted to be actuated by the act of establishing connection with the trunk line to alternate between two contact points, one contact of each switch being connected to one pole of a grounded battery, and the other contact of each switch being connected to earth, and a conductor including an indicator joining the levers of the said switches, whereby the circuits are altered to actuate the indicator when either switch is operated, substantially as described.

6. The combination with a transfer line terminating in a spring jack at one end, and in a terminal plug at the other, of a switch controlled by the spring jack, and a cord switch controlled by the terminal plug, each of said switches having a lever adapted to be alternated between a ground contact and a contact connected to one pole of a grounded battery, both of said contacts being connected to the same pole of the same battery, or to similar poles of an equal battery, and a conductor including an indicator at the receiving station connecting the said levers, whereby when either switch is in its normal position, the other being in its alternate position, the said indicator is operated, substantially as described.

7. The combination with a spring jack at one switchboard, of a local branch circuit extending from said spring jack to earth through an annunciator at another switchboard and a ed therewith at another switchboard, a normally closed cord switch socket for said plug, and an annunciator thereat, normally open contact points upon said spring jack adapted to be closed together when a plug is inserted into the jack, and a conducting circuit including said contact points upon the spring jack, the contact points of the cord switch, said annunciator, and a battery, whereby the annunciator is operated when a plug is inserted into the spring jack and its circuitis opened when the terminal plug is removed from its socket, substantially as described.

10. The combination with a spring jack at one switchboard, provided with normally closed contact points adapted to be separated when a plug is inserted into the jack, of a terminal plug at another switchboard connected with the line spring of said jack, an annunciator at said second board, a local circuit extending from ground through saidcontact points on the spring jack, the annunciator, and a source of electricity and connected with said terminal plug, and a telephone line connected to earth and terminating in a spring jack into which said terminal plug is inserted, substantially as described.

In witness whereof I hereunto subscribe my name this 9th day of October, A. D. 1890.

CHARLES E. SORI-BN'ER.

WVitnesses:

ELLA EDLER, GEORGE P. BARTON. 

